The invention relates to an apparatus for opening one layer of a tube-like material web, comprising a cutting means and guiding means for guiding the material web.
Such an apparatus is disclosed for example in EP-A-0 269 145. In this known apparatus the cutting means includes a perforating knife which perforates both layers of the tube-like material web, whereafter the perforation in the upper layer is torn open by mechanical auxiliary means. This known apparatus has the disadvantage that the adjustment of the apparatus to the material web to be used is rather cumbersome, whereas the construction of the apparatus is complicated due to the required mechanical auxiliary means.
U.S. Pat. No. 4,586,318 discloses an apparatus of the above-mentioned type, wherein the cutting means includes a heated cutting wire which is pressed on said one layer of the tube-like material web. This known apparatus shows the disadvantage that the tube-like material web must be guided around a separation plate for separating both layers.